NUCULIDiE. 37 



rotuiidato-acuminataj radio iiuUo impressa, subla^vigata, cute niti- 

 dissima validu flavcsccntc-olivacea iiiduta. Margo dorsalis aiiticus 

 vix declivis ; posticus declivis, subrectus ; ventralis anticc arcuatus 

 et multum acclivis. Nates acutissima;, baud autem cniiucntes. 

 Arefc dorsales baud definitai : lunula planulata : areas labia cariiiato- 

 protrusa. — Somewbat elliptical, very inequilateral, raucb com- 

 pressed, covered by polisbed yellowisb-olive strong epidermis, 

 devoid of umbonal ridge or anterior ray, smootli, except for tbe 

 wrinkles of increase. Anterior side mueb produced, its extremity 

 somewbat tapering, unsyrametrically rounded. Posterior side 

 short, quickly tapering to a rounded peak wbicb lies ratber above 

 tban below the middle. Front dorsal slope almost horizontal, at 

 first straigbtish, eventually convex. Hinder dorsal slope moderate, 

 straigbtish. Ventral margin obliquely arching up in front, merely 

 broadly convex iu tbe middle, subarcuatedly rising behind. Beaks 

 peculiarly sharp, yet not prominent. Dorsal areas undefined ; the 

 front one flattened, sometimes impressed ; lips of tbe escutcheon 

 carinately pouting. Teeth rather few (about nine and twelve at 

 most) on either side of tbe cartilage-pit, which latter is depressed, 

 and has its base rounded. — There is some faint trace of an in- 

 dented ray near the hinder extremity. 



63. L. SAPOTiLLA, Gould, f. 16. — T. asquilateralis, subventri- 

 cosa, leevis, subovalis, postiee obtuse acuminata et pauUulum 

 subrostrata, cute polita luteo-subvirescente induta. Margo dorsalis 

 auticus arcuatus, vix declivis ; posticus rectior, leviter declivis ; 

 ventraHs antice subito et obhque accHvis, postiee subsinuatus. 

 Areas dorsales baud definitee. Nates baud emiuentes. — Suboval, 

 subventricose at tbe umboes, only sbghtly gaping at the extremi- 

 ties, pure white imder a polisbed fugacious oil-yellow cuticle, 

 smooth, or at most with wrinkles of increase. Sides equal or 

 very nearly so ; the anterior, if either, the shorter, unsymmetrically 

 rounded ; the posterior bluntly peaked, aud, from the slight ven- 

 tral flexure, a little subrostrated, the tip rounded. Front dorsal 

 edge arched, scarcely sloping : hinder one straigbter, a little 

 sloping:. Ventral margin a little convex in the middle, abrujitly 

 and obliquely ascending in front, convexly rising behind, forming 

 a shallow sinus near the extremity. Dorsal areas undefined. 

 Teeth numerous (about eighteen) on each side.* 



* I have not seen the fry of this shell, but suspect it must somewhat resemble a 

 species of which I am unable to procure a spei-iinen, the — 



L. OBESA, Slimpson Froc. Bost. Nat. Hist. fsor. iv. /). 113; S/ie/ls N. Eni/l. 

 p. 10, pi. i, I'. 1). — " T. parva, tenuis, ovalis, inicquilaleralis, postiee lonirior, epiiler- 

 mide uitida, tcuuistriata ; apieibus j)iu-vis ; marline ventral] inodice arcuato ; .areola 



